The CCNet resource pack includes custom armour textures that can be activated by renaming armour items in a certain way.
To see these textures, you need to install Optifine or the CITResewn mod for Fabric.
The following armour textures are based on uniforms worn during World War One:
American for the USAAustro for the Austro-Hungarian EmpireBelgian for BelgiumBritish for BritainFrench for FranceGerman for the German EmpireJapanese for JapanOttoman for the Ottoman EmpireRussian for the Russian EmpireItalian for the Kingdom of ItalyFinnish for Finland
The following armour textures have been submitted by players for their own nations:
Roman for Imperium Romanum armourSahara for Sub-Sahara Syndicate armour, weapons and toolsCultistNetherite, CultistDiamond, CultistIron and CultistGold for Cultist Empire armourCultist for Cultist Empire weapons, tools and shieldThracian for Thracian Dominion armour and swordsNasrid for Great Nasrid Emirate armour
You can change the texture of leather horse armour by dyeing it a specific colour.
Unlike player armour, this does not require Optifine or CITResewn - the CCNet resource pack itself is sufficient.
Note: These will not show for players using 1.20.5 and above.